(1) To identify industries, such as construction, shipbuilding, railroad, manufacturing companies, and unions involved in welding operations for exposure assessments where the potential for substantial manganese exposure exists; (2) develop methods to identify manganese compounds and different valence states, based on selective solubility with various welding fumes matrices; and (3) characterize welding fume exposures based on welding-associated jobs, tasks, and processes.

To assess exposure to nine alternative flame retardants plus a panel of polybrominated diphenyl ethers. Exposure will be assessed among workers involved in the manufacture, installation, or use of goods containing these nine alternative flame retardants. Worksite categories included in the study are manufacture of products that use flexible polyurethane foams, plastics, or resins; fabrication and manufacture of rigid polystyrene foam; cutting, installing, or spraying polyurethane foam insulation at construction sites; using gymnasiums; manufacture of wire harnesses or printed circuit boards; and the fire service industry. This study will compare exposures among industries, processes, and tasks; determine the route of exposure; and make recommendations to reduce exposures. These data will be used to determine exposure levels of workers in different occupations and how they relate to the general population by comparison to the National Health and Nutrition Examination Survey data. The results will aid in the design of toxicological studies, understanding and use of toxicological studies, and risk assessment.

To evaluate the levels of occupational chemical exposure among workers who are using coal tar-based pavement sealants. Coal tar is sometimes used as a base material for blacktop pavement sealants, accounting for as much as 35 percent of the formulation in some of these products. Coal tar is a byproduct of the production of coke, which is needed for steel production. Coal tar pitch volatiles are a mixture of chemicals that can evaporate into air from products containing coal tar, including coal tar pavement sealants. These coal tar pitch volatiles contain several chemicals known as polycyclic aromatic hydrocarbons (PAHs). The focus of this study is on the assessment of occupational exposure to PAHs among coal tar sealant workers. This study will provide data regarding levels of exposure to airborne chemicals that will be compared to current NIOSH recommended exposure limits for coal tar pitch volatiles, and will report results for specific PAH chemicals using NIOSH analytical methods. PAHs will be measured in dermal wipe samples, and PAH metabolites will be measured in biological samples collected from workers to characterize levels present in this workforce.

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